CN110636894B

CN110636894B - Osmotic pressure assisted reverse osmosis membrane and module

Info

Publication number: CN110636894B
Application number: CN201780088379.8A
Authority: CN
Inventors: Q·魏; E·贝克; J·韦伯利; G·卡米格纳尼
Original assignee: Trevi Systems Inc
Current assignee: Trevi Systems Inc
Priority date: 2017-01-20
Filing date: 2017-01-20
Publication date: 2022-06-03
Anticipated expiration: 2037-01-20
Also published as: US11839853B2; CN110636894A; US20210275968A1; WO2018136077A1; EP3570965A4; EP3570965A1; US20240139681A1

Abstract

The present invention provides membranes and filtration modules for producing concentrated and diluted feed streams during operation in a water purification or wastewater treatment system. A filtration module is provided that includes a semi-permeable membrane having a first side configured to receive a flow of a first feed solution from a first feed solution source and a second side configured to receive a flow of a second feed solution from a second feed solution source. The semi-permeable membrane may be configured to operate at a hydrostatic pressure on the second side of the membrane that is about 1% to about 40% of the hydrostatic pressure on the first side of the membrane, and in some cases may exhibit a salt rejection of about 60% to about 90% during operation.

Description

Osmotic pressure assisted reverse osmosis membrane and module

Technical Field

The present disclosure relates to the purification, clarification or desalination of seawater, brackish water, wastewater, industrial water, produced water and/or contaminated water using membranes and filter modules suitable for osmotic pressure assisted reverse osmosis processes. The present disclosure also relates to forming a concentrated feed solution using an osmotically-assisted reverse osmosis membrane and a filter module and producing purified water as a byproduct.

Background

Some membranes allow solvent molecules to pass through, but not solute molecules. Such membranes are called semi-permeable. Semipermeable membranes can be used in desalination and water purification technologies.

Forward osmosis is known in the art and has been the subject of recent research due to the potential for future fresh water shortages and the corresponding increase in demand for cost-effective desalination and water purification technologies. Seawater, brackish water, or other contaminated water may be purified by extracting the water (solvent) through a semi-permeable membrane that rejects the passage of salts and other contaminants (solutes). In a forward osmosis process, water is extracted through a semi-permeable membrane using an extraction solution having a higher osmotic pressure than the feed. The forward osmosis process does not purify the water. Forward osmosis simply moves water from one group of solutes to another.

Reverse osmosis processes have also been applied to water purification technology. In particular, reverse osmosis has been used to desalinate seawater, brackish water, or other contaminated water by removing salts from the water to produce potable or other industrially useful water. In forward osmosis, solvent flows from a dilute solution through a semi-permeable membrane to a more concentrated solution. The osmotic process can be stopped by applying a pressure equal to the osmotic pressure to the more concentrated solution. By applying even more pressure, the permeation process can be reversed. In this case, the solvent flows from a concentrated solution (such as seawater) across the semi-permeable membrane to a more dilute solution. The hydrostatic pressure requirements of reverse osmosis can make reverse osmosis energy costly. In addition, the evaporation process and crystallization process involved in a Zero Liquid Discharge (ZLD) system for concentrating solutes beyond the concentration level of conventional RO are also costly. Accordingly, there is a need for membranes and filtration modules suitable for use in devices and systems that can reduce energy costs or increase the efficiency of reverse osmosis systems and other water purification systems.

Drawings

Embodiments of the present application are described, by way of example only, with reference to the accompanying drawings, in which:

fig. 1 is a diagram of a filtration module and membrane suitable for use in an osmotically-assisted reverse osmosis (OsARO) system according to an example embodiment of the present disclosure;

fig. 2 is a diagram of a multi-stage OsARO system according to an example embodiment of the present disclosure;

fig. 3A-3E are a series of graphs comparing an OsARO system with a Reverse Osmosis (RO) system, a Forward Osmosis (FO) system, a Pressure Retarded Osmosis (PRO) system, and a pressure assisted FO (pafo) system, according to an example embodiment of the present disclosure;

FIG. 4 is a diagram of a flat sheet membrane filtration module having sealing elements separating permeate tubes and characterized by a U-shaped flow pattern within permeate spacers suitable for use in an osmotically assisted reverse osmosis (OsARO) system according to an exemplary embodiment of the present disclosure;

FIG. 5 is a diagram of a flat sheet membrane filtration module having receiving and collection chambers within a permeate spacer suitable for use in an osmotically-assisted reverse osmosis (OsARO) system according to an exemplary embodiment of the present disclosure;

FIG. 6 is a diagram of a flat sheet membrane filtration module suitable for use in an osmotically-assisted reverse osmosis (OsARO) system having a second tube according to an exemplary embodiment of the present disclosure;

FIG. 7 is an exploded view of a flat sheet membrane envelope according to an exemplary embodiment of the present disclosure;

FIG. 8 is an exploded view of a flat sheet membrane envelope with feed spacers according to an exemplary embodiment of the present disclosure;

FIG. 9 is a diagram of a spiral wound flat sheet membrane module according to an example embodiment of the present disclosure; and

fig. 10 is a diagram of a tubular hollow fiber membrane module according to an example embodiment of the present disclosure.

It should be understood that the aspects are not limited to the arrangements and instrumentality shown in the attached drawings.

Detailed Description

It will be appreciated that for simplicity and clarity of illustration, where considered appropriate, reference numerals have been repeated among the figures to indicate corresponding or analogous elements. Furthermore, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein may be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the relevant features described in connection therewith. Additionally, this description is not to be taken as limiting the scope of the embodiments described herein. The figures are not necessarily to scale and the proportions of certain parts have been exaggerated in order to better illustrate the details and features of the present disclosure.

Several definitions that apply throughout this disclosure will now be presented. The term "OsARO" refers to osmosis-assisted reverse osmosis and may also be referred to as forward osmosis pretreatment reverse osmosis (FO-PRO) or forward osmosis recovery membrane (FO-ORM). The term "coupled" is defined as directly connected or indirectly connected through intervening components and is not necessarily limited to physical connections. The term "fluidically coupled" is defined as connected directly or indirectly through intermediate components, and is not necessarily limited to physical connections, but rather connections that regulate the transfer of solutions, dispersions, mixtures or other fluids between the components so described. The connection may be such that the objects are permanently or reversibly connected. The terms "comprising," "including," and "having" are used interchangeably in this disclosure. The terms "comprising," "including," and "having" are intended to be inclusive and not necessarily limited to the thing so described.

As used herein, the terms "purification", "purified" or "purification" refer in their various forms to one or more processes that produce water having at least the following properties: the purity is gradually increased and/or the solute concentration or contaminant concentration is gradually decreased. Thus, the terms "purifying", "purified" or "purification" do not necessarily refer to the production of water having a particular purity or a particular solute concentration, but rather, the terms are used to refer to the production of water having at least the following properties as a result of the disclosed methods and techniques: the purity is gradually increased and/or the solute concentration or contaminant concentration is gradually decreased.

As used herein, the term "stream" in its various forms (including its use in the term "feed stream") refers to a solution that can flow into or be received in a portion or component of an apparatus or system of the present disclosure, and is not limited to a solution introduced into an apparatus or system, or a portion thereof, under continuous flow, but may also include a solution received in an apparatus or system for a period of time, such as may be employed in a series of batch processes.

As used herein, the term "permeate channel" refers to any channel, passageway, or reservoir in a permeate spacer that is capable of receiving a flow of a permeate solution and/or a second feed solution and is also capable of providing a flow of a permeate solution and/or a second feed solution through the permeate spacer. As used herein, the term "permeate channel" may equally refer to a single passage, a plurality of passages, or a network of passages capable of receiving a flow of permeate solution and/or a second feed solution and also capable of providing a flow of permeate solution and/or a second feed solution through the permeate spacer.

According to at least one aspect of the present disclosure, a filtration module is provided. The filtration module can include a semi-permeable membrane having a first side and a second side, wherein the first side is configured to receive a flow of a first feed solution from a first feed solution source and the second side is configured to receive a flow of a second feed solution from a second feed solution source. The filter module may further comprise a semi-permeable membrane: the semi-permeable membrane is configured to transfer a solvent of a first feed solution stream from a first side of the membrane to a second side of the membrane in a permeate solution upon application of hydrostatic pressure to the first and second sides of the membrane. The semi-permeable membrane may be configured to operate at a hydrostatic pressure on the second side of the membrane of about 1% to about 40% of the hydrostatic pressure on the first side of the membrane. In at least some cases, the membrane can be configured to operate with a pressure on the first side of the membrane from about 10 bar to about 120 bar and a pressure on the second side of the membrane from about 2 bar to about 20 bar. In at least some instances, the membrane can exhibit a rejection rate of about 60% to about 90% during operation in a desalination, ZLD, or near ZLD wastewater treatment system.

In at least one other aspect of the present disclosure, a filtration module is provided that includes a first chamber and a second chamber. A semi-permeable membrane is disposed at an interface between the first chamber and the second chamber. The semi-permeable membrane has a first side in fluid communication with the first chamber and a second side in fluid communication with the second chamber. The first chamber is configured to receive a flow of a first feed solution from a first feed solution source, and the second chamber is configured to receive a flow of a second feed solution from a second feed solution source. The semi-permeable membrane is configured to transfer a solvent of a first feed solution stream from a first side of the membrane to a second side of the membrane in a permeate solution upon application of hydrostatic pressure to the first and second sides of the membrane. The semi-permeable membrane may be configured to operate at a hydrostatic pressure on the second side of the membrane of about 1% to about 40% of the hydrostatic pressure on the first side of the membrane. In at least some cases, the membrane can be configured to operate with a pressure on the first side of the membrane of about 10 bar to about 120 bar and a pressure on the second side of the membrane of about 2 bar to about 20 bar. In at least some cases, the membrane may exhibit a salt rejection of about 60% to about 90% during operation in a desalination, ZLD, or near ZLD wastewater treatment system.

Fig. 1 illustrates an apparatus 100 according to an example embodiment of the present disclosure. As depicted in fig. 1, the apparatus 100 includes an OsARO filtration module 150 for concentrating the first feed solution 141 while diluting the second feed solution 142 with the semi-permeable membrane 115. The OsARO filtration module comprises a first chamber 131 and a second chamber 132 opposite the first chamber 131. A semi-permeable membrane 115 is disposed at the interface between the first chamber 131 and the second chamber 132. The semi-permeable membrane 115 has a first side 121 in fluid communication with the first chamber 131 and a second side 122 in fluid communication with the second chamber 132.

During operation, the OsARO filtration module 150 is configured to receive a first feed solution stream 141 having a solute concentration of C1 and an osmotic pressure of pi (C1). The first feed solution stream 141 is directed to the first chamber 131 and the first side 121 of the semi-permeable membrane 115 while being subjected to hydraulic pressure P1. In at least some cases, first feed solution stream 141 enters first chamber 131 via an inlet port (such as inlet port 181 shown in fig. 1).

The OsARO filtration module 150 is also configured to receive a second feed solution stream 142 into the second chamber 132 and onto the second side 122 of the semi-permeable membrane 115. The second feed solution stream 142 has a solute concentration of C2 and an osmotic pressure pi (C2) that is less than or equal to the osmotic pressure pi (C1) of the first feed solution stream 141 fed on the opposite first side 121 of the semi-permeable membrane 115. The second feed solution stream 142 is fed into the second chamber 132 and onto the second side 122 of the semi-permeable membrane 115 at a hydraulic pressure P2 that is less than the hydraulic pressure P1 of the first feed solution stream 141. In some cases, the solute concentration C1 of the first feed solution stream 141 is greater than the solute concentration C2 of the second feed solution stream 142. In other cases, the solute concentrations C1 and C2 may be the same. In at least some cases, the second feed solution stream 142 enters the second chamber 132 via an inlet port (such as the inlet port 182 shown in fig. 1).

Due to the balance of hydraulic and osmotic pressures, the solvent is transferred from the first compartment 131 to the second compartment 132 as permeate 112 via the semi-permeable membrane 115, thereby concentrating the first feed solution stream 141 (C1)_{Go out}>C1_Into) To form a concentrated first feed solution stream 171 while diluting a second feed solution stream 142 (C2)_Into>C2_{Go out}) To form a diluted second feed solution stream 172. In accordance with the disclosed technique, a Reverse Osmosis (RO) process is assisted by the osmotic pressure provided by second feed solution stream 142, resulting in an osmotically-assisted reverse osmosis (OsARO) process that is more energy efficient.

In accordance with at least one aspect of the present disclosure, the first chamber 131 of the OsARO filtration module 150 can be fluidly coupled with a first feed solution source 161 configured to flow a first feed solution stream 141 onto the first chamber 131 and the first side 121 of the semi-permeable membrane 115. First feed solution source 161 can be a high pressure pump, as depicted in fig. 1, or in at least some cases can be a first chamber or a second chamber of another OsARO filtration module. In at least some cases, first feed solution source 161 can be a reverse osmosis component or a forward osmosis component.

Similarly, in at least some instances, the second chamber 132 of the OsARO filtration module 150 can be fluidly coupled with a second feed solution source 162 configured to flow a second feed solution stream 142 onto the second chamber 132 and the second side 122 of the semi-permeable membrane 115. The second feed solution source 162 may be a low or high pressure pump, as depicted in fig. 1, or in at least some cases may be the first or second chamber of another OsARO filtration module, a reverse osmosis component, or a forward osmosis component.

In accordance with at least one aspect of the present disclosure, the osmotic pressure of the second feed solution stream 142 is greater than the osmotic pressure of the permeate 112. In at least some instances, the first feed solution source 161 and the second feed solution source 162 can be configured to create a pressure differential between the hydrostatic pressure of the first feed solution stream 141 and the hydrostatic pressure of the second feed solution stream 142 sufficient to cause solvent to transfer from the first side 121 of the semi-permeable membrane 115 to the second side 122 of the semi-permeable membrane 115 in the form of the permeate 112. In some cases, first feed solution source 161 and second feed solution source 162 may be configured to vary the pressure differential according to the osmotic pressure of second feed solution stream 142.

In accordance with at least one aspect of the present disclosure, the concentrated first feed solution stream 171 may exit the first chamber 131 of the OsARO filtration module 150 at an outlet port (such as outlet port 191 depicted in fig. 1). Similarly, the diluted second feed solution stream 172 may exit the second chamber 132 of the OsARO filtration module 150 at an outlet port (such as outlet port 192 depicted in fig. 1). Although the OsARO filtration module 150 depicted in fig. 1 is depicted as having only a single inlet port and outlet port for each chamber, a first chamber or a second chamber having multiple inlet ports and/or outlet ports is still within the spirit and scope of the present disclosure.

In accordance with at least one aspect of the present disclosure, the concentrated first feed solution stream 171 and/or the diluted second feed solution stream 172 may be fed to another OsARO filtration module or a reverse osmosis or forward osmosis component. In at least some cases, the first feed solution source 161 can be configured to recycle the concentrated first feed solution stream 171, or a portion thereof, to the first side 121 of the semi-permeable membrane 115. In some cases, the second feed solution source 162 can be configured to provide at least a portion of the concentrated first feed solution stream 171 to the second side 122 of the semi-permeable membrane 115.

In accordance with at least one aspect of the present disclosure, first feed solution stream 141 may be a contaminated solution. In some cases, the contaminated solution may be divided into at least two portions, one portion forming the first feed solution stream 141 and the other portion forming the second feed solution stream 142. In such cases, the first feed solution source 161 and the second feed solution source 162 are each configured to provide portions of the same contaminated solution to the first side 121 and the second side 122, respectively, of the semi-permeable membrane 115.

The first feed solution stream 141 and the second feed solution stream 142 may have the same or different chemical compositions and may be at the same temperature or different temperatures. The first and second feed solution streams may contain many different solution components, some of which may contribute to osmotic pressure and others of which may not. Any solution that creates osmotic pressure can be used in the disclosed devices, systems, and methods.

In at least some cases, the solvent of either the first or second feed solution streams may be water, an inorganic salt, a polar organic solvent (such as methanol or ethanol), or any other suitable solvent. In some cases, a feed solution stream with inorganic salt solutes such as sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl) can be used₂) Magnesium carbonate (MgCO)₃) Magnesium sulfate (MgSO)₄) Calcium chloride (CaCl)₂) Calcium sulfate (CaSO)₄) Calcium carbonate (CaCO)₃) Potassium acetate (KAc) or calcium magnesium acetate (CaMgAc). In other cases, a feed solution stream with an inorganic salt solute, including ionic species such as transition metals, lanthanides, and actinides, may be used. In other cases, feeds with inorganic salt solutes may be usedA stream of solution, the inorganic salt solution comprising substances such as cyanide, nitrate, nitrite, sulfate, sulfite, sulfonate, hydroxide, phosphate, phosphite, halide, acetate, arsenide, amine, carboxylate, and nitro species. In some cases, when water is a solvent, organic compound solutes with good water solubility, such as alcohols, dioxane, acetone, Tetrahydrofuran (THF), Dimethylformamide (DMF), and Dimethylsulfoxide (DMSO), may be used. In some cases, organic compound solutes with water solubility, such as aromatics (e.g., toluene and benzene), linear alkanes or alkenes (e.g., hexane or octane), chlorinated solvents (e.g., methylene Chloride (CH), can be used as solutes in the feed solution stream ₂Cl₂) Organic sulfonates, and organic acids. In some cases, polymeric solutes such as, but not limited to, sugars, Ethylene Oxide (EO), Propylene Oxide (PO), polyethylene glycol (PEG), poly (acrylic acid), poly (vinyl alcohol) poly (ethylene oxide), poly (vinyl acid), poly (styrene sulfonate), poly (acrylamide) -based polyelectrolytes, poly (diallyldimethylammonium chloride), poly (allylamine hydrochloride), poly (vinylpyrrolidone), poly (N-isopropylacrylamide), poly (alkyl acrylates), polyalkylacrylic acid, poly (2-oxazoline), and polyethyleneimines, and copolymers or block copolymers thereof, or any combination thereof, may be used.

Fig. 2 illustrates an apparatus 200 according to an example embodiment of the present disclosure. As depicted in fig. 2, the apparatus 200 includes a plurality of OsARO filtration modules 250-253 fluidly coupled to one another in series for successive separation steps or stages, wherein the initial first feed solution stream 241 may be incrementally concentrated to higher concentrations. Each of the OsARO filtration modules 250-253 includes a first chamber 231-234, a second chamber 236-239, and a semi-permeable membrane 215-218 disposed at the interface between the first chamber 231-234 and the second chamber 236-239. Each semi-permeable membrane 215-218 has a first side 221-224 in fluid communication with a first chamber 231-234 and a second side 226-229 in fluid communication with a second chamber 236-239.

During operation, the first OsARO filtration module 250 is configured to receive an initial first feed solution stream 241. The initial first feed solution stream 241 is directed to the first chamber 231 of the first filtration module 250 and the first side 221 of the semi-permeable membrane 215 while being subjected to hydraulic pressure. As depicted in fig. 2, an initial first feed solution stream 241 enters the first chamber 231 from a first feed solution source 261 via an inlet port 281. The first filtration module 250 is also configured to receive a second feed solution stream 246 from a second feed solution source 262 into the second chamber 236 and onto the second side 226 of the semi-permeable membrane 215. The first feed solution source 261 and the second feed solution source 262 may be high pressure pumps, or may be a reverse osmosis unit or a forward osmosis unit.

By way of example only, FIG. 2 depicts an initial first feed solution stream 241 having a solute concentration of initially 65g/l NaCl, matching that of the second feed solution stream 246. The solute concentration of the feed solution stream may be any value as long as the osmotic pressure of the second feed solution stream 246 is less than or equal to the osmotic pressure of the original first feed solution stream 241, and the solute concentration of the second feed solution stream 246 is sufficient to assist the reverse osmosis process by reducing the required hydrostatic pressure necessary to produce the permeate. In at least some instances, it is advantageous to use a second feed solution stream (as depicted in fig. 2) having a solute concentration approximately equal to that of the first feed solution stream because the second feed solution stream provides a significant osmotic pressure whereby the reverse osmosis process is facilitated. In at least some cases, the osmotic pressure difference across the membrane can be reduced to near zero in order to reduce the hydraulic pressure necessary to perform the process.

During operation, the initial first feed solution stream 241 exerts hydraulic pressure on the first side 221 of the semi-permeable membrane 215 such that solvent passes from the first side 221 of the semi-permeable membrane 215 to the second side 226 of the semi-permeable membrane 215, thereby producing a concentrated first feed solution stream 242 in the first chamber of the first module 250 and a diluted second feed solution 271 in the second chamber 236. The example embodiment presented in FIG. 2 shows that during operation or first phase of the first module 250 of the apparatus 200, an initial first feed solution stream 41 having a solute concentration of 65g/l NaCl is concentrated to 105g/l NaCl. As depicted in fig. 2, the concentrated first feed solution is fed as a third feed solution stream 242 into the first chamber 232 of the second OsARO filtration module 251 where it is concentrated to 145g/l NaCl as a result of the same process described with reference to the first module 250. The concentrated third feed solution stream is then fed as a fifth feed solution stream 243 into the first chamber 233 of the third OsARO filtration module 252 where the fifth feed solution stream 243 is concentrated to 185g/l NaCl. The concentrated fifth feed solution stream is then fed as a seventh feed solution stream 244 into the first chamber 234 of the fourth OsARO filtration module 253 where it is concentrated to a target concentration of 225g/l at the outlet port 294. In each of the filter modules 250-.

In at least some cases, feed solution stream 247-249 can be fed from feed solution source 263-265 to second chamber 237-239 of module 251-253. In some cases, feed solution source 263-265 may be a low pressure pump or a high pressure pump. In other cases, feed solution stream 247-249 can comprise at least a portion of the concentrated feed stream 242-244 of the previous module. In such cases, the feed solution source 263-265 may be the first chamber 231-233 of the previous module 250-252. For example, the fourth feed solution stream 247 may comprise at least a portion of the concentrated first feed solution stream 242 from the first chamber 231 of the first module 250.

In accordance with at least one aspect of the present disclosure, the diluted feed solution stream 271-274 may be fed to another OsARO filtration module or reverse osmosis component, as described with reference to additional exemplary embodiments provided below. For example, the diluted feed solution stream 272 from the second chamber 237 of the second module 251 can be fed to the second chamber 236 of the first filtration module 250 to at least partially form the second feed solution stream 246.

As depicted in fig. 2, the first chambers 231-234 of the OsARO filter modules 250-253 have inlet ports 281-284 that provide access paths for the feed solution stream into the first chambers 231-234. In addition, the first chamber 231-. Similarly, the second chamber 236-. In some cases, the OsARO modules may be configured with multiple inlet ports and multiple outlet ports for each of the respective feed solution streams. Furthermore, these OsARO filtration modules can be used in a continuous process, a batch process, or a semi-batch process. The feed solution stream may be passed through the membrane only once, or through the membrane multiple times by recovery and recirculation, in each filtration module of each process. Furthermore, the hydraulic pressure applied to the feed solution stream may be kept constant or may be varied during the respective process step.

In accordance with at least one aspect of the present disclosure, the apparatus 200 depicted in fig. 2 may be used to perform a process of concentrating a solute (such as a contaminant) in a solution comprising a solvent and the solute. The process includes providing a first filtration module 250 fluidly coupled to a first feed solution source 261 and a second feed solution source 262. The first filter module 250 may include a first chamber 231 and a second chamber 236. The first filtration module 250 can also include a semi-permeable membrane 215 disposed at the interface between the first chamber 231 and the second chamber 236. The semi-permeable membrane 215 may have a first side 221 in fluid communication with the first chamber 231 and a second side 226 in fluid communication with the second chamber 236. The process also includes introducing a first feed solution stream 241 from a first feed solution source 261 onto the first chamber 231 and the first side 221 of the semi-permeable membrane 215.

The process also includes introducing a second feed solution stream 246 from a second feed solution source 262 onto the second chamber 236 and the second side 226 of the semi-permeable membrane 215. The osmotic pressure of the first feed solution stream 241 is greater than or equal to the osmotic pressure of the second feed solution stream 246. The process further comprises applying hydrostatic pressure on the first side 221 of the semi-permeable membrane 215 such that the solvent passes from the first side 221 to the second side 226 of the semi-permeable membrane 215, thereby producing a concentrated feed solution stream 242 in the first chamber 231 and a diluted second feed solution stream 271 in the second chamber 236.

In at least some instances, the process can further include selecting the osmotic pressure of the second feed solution stream 246 so as to reduce the hydrostatic pressure required to transfer the solvent from the first side 221 to the second side 226 of the semi-permeable membrane 215, thereby producing a concentrated feed solution stream 242 and a diluted second feed solution stream 271. In other cases, the osmotic pressure of the second feed solution stream 246 can be a predetermined osmotic pressure selected to reduce the hydrostatic pressure necessary to pass the solvent from the first side 221 to the second side 226 of the semi-permeable membrane 215. In some cases, the osmotic pressure of the second feed solution stream 246 may be selected to be greater than the osmotic pressure of the permeate solution in order to reduce the hydrostatic pressure required to pass the solvent from the first side 221 to the second side 226 of the semi-permeable membrane 215.

In accordance with at least one aspect of the present disclosure, the process can further include recycling the concentrated first feed solution stream 242, or a portion thereof, to the first side 221 of the semi-permeable membrane 215. The process can also include recycling at least a portion of the concentrated first feed solution stream 242 to the second side 226 of the semi-permeable membrane 215.

In at least some cases, the process further includes providing a second filtration module 251 fluidly coupled to the first module 250 and a fourth feed solution source 263. The second module 251 includes a first chamber 232 and a second chamber 237. The second filtration module 251 further comprises a semi-permeable membrane 216 disposed at the interface between the first chamber 232 and the second chamber 237. The semi-permeable membrane 216 includes a first side 222 in fluid communication with the first chamber 232 and a second side 227 in fluid communication with the second chamber 237. The process also includes introducing a third feed solution stream 242 from the first chamber 231 of the first filtration module 250 to the first chamber 232 of the second filtration module 251. The third feed solution stream 242 can comprise at least a portion of the concentrated first feed solution stream. The process also includes introducing a fourth feed solution stream 247 from a fourth feed solution source 263 onto the second chamber 237 of the second filtration module 251 and the second side 227 of the semi-permeable membrane 216. The osmotic pressure of the third feed solution stream 242 is greater than or equal to the osmotic pressure of the fourth feed solution stream 247. The process further includes applying hydrostatic pressure on the first side 222 of the semi-permeable membrane 216 of the second module 251 such that solvent is transferred from the first side 222 of the semi-permeable membrane 216 to the second side 227 of the semi-permeable membrane 216, thereby producing a concentrated third feed solution stream 243 in the first chamber 232 of the second module 251 and a diluted fourth feed solution stream 272 in the second chamber 237 of the second module 251.

The fourth feed source 263 may be a high pressure pump or may be the first chamber 231 of the first module 250. In such cases, the fourth feed solution stream 247 can comprise at least a portion of the concentrated feed solution stream 242 from the first chamber 231 of the first filtration module 250.

In addition to providing a process for concentrating a solution, the present disclosure also provides a process for purifying a solvent from a solute solution. For example, an OsARO filtration module depicted in fig. 1 and 2 and described above may be combined with a Reverse Osmosis (RO) component and a Forward Osmosis (FO) component to produce a purified solvent product, such as a water permeate. More specifically, a process for purifying a solvent may include providing a Forward Osmosis (FO) component fluidly coupled to a Reverse Osmosis (RO) component and a filtration module. The filtration module can include a first chamber fluidly coupled to the RO and FO components, and a second chamber fluidly coupled to the RO component. The filtration module may further comprise a semi-permeable membrane disposed at an interface between the first chamber and the second chamber. The semi-permeable membrane may include a first side in fluid communication with the first chamber and a second side in fluid communication with the second chamber.

The process also includes introducing the contaminated FO feed solution to the FO section. The contaminated FO feed solution contains a solvent contaminated with one or more solutes. The process also includes having the FO component produce a concentrated FO feed solution stream and a diluted draw solution from the contaminated FO feed solution stream. The process may also include introducing the diluted draw solution to an RO component to form at least a portion of an RO feed solution stream. The process may also include causing the RO unit to produce a permeate solution and a concentrated RO feed solution stream from the RO feed solution stream. The permeate solution comprises the purified solvent recovered according to the process.

The process can also include introducing a first feed solution stream from the RO component to the first chamber of the filtration module and onto the first side of the semi-permeable membrane. The first feed solution stream comprises at least a portion of the concentrated RO feed solution stream. The process can also include introducing a second feed solution stream from the RO unit onto the second chamber of the filtration module and the second side of the semi-permeable membrane. The second feed solution also comprises at least a portion of the concentrated RO feed solution stream. The osmotic pressure of the first feed solution stream may be approximately equal to the osmotic pressure of the second feed solution stream. Alternatively, the osmotic pressure of the first feed solution stream may be greater than the osmotic pressure of the second feed solution stream.

The process may further comprise applying hydrostatic pressure on the first side of the semi-permeable membrane such that the solvent is transferred from the first side of the semi-permeable membrane to the second side of the semi-permeable membrane, thereby producing a concentrated first feed solution stream in the first chamber and a diluted second feed solution stream in the second chamber. The process can also include introducing at least a portion of the diluted second feed solution stream from the second chamber of the module to the RO component for use as at least a portion of the RO feed solution stream. The process can also include introducing at least a portion of the concentrated first feed solution stream from the first chamber of the filtration module to the FO component to form at least a portion of the draw solution.

Fig. 3A-3E illustrate the differences between the OsARO apparatus and techniques disclosed herein and conventional techniques of Reverse Osmosis (RO), Forward Osmosis (FO), Pressure Retarded Osmosis (PRO), and Pressure Assisted Forward Osmosis (PAFO) processes. The OsARO process is different from the RO, FO, PRO, and PAFO processes used in the art. As shown in fig. 3A-3E, each of these processes uses a semi-permeable membrane to separate one or more solutes from a solution.

The conventional processes mentioned above can be divided into two categories depending on the direction of the permeate flow. In FO, PRO and PAFO the permeate flows from the low osmotic pressure mixture side (pi (C2)) to the high osmotic pressure mixture side (pi (C1)) of the semi-permeable membrane. Generally, in an FO system, the hydraulic pressure applied on both sides of the membrane is equal. In a PRO system, feed 1 is introduced at a hydraulic pressure P1 and a osmotic pressure π (C1) that are higher than the hydraulic pressure P2 and the osmotic pressure π (C2) of feed 2, resulting in a permeate flow from feed 2 to feed 1. In a PAFO system, the hydraulic pressure P2 of feed 2 is higher than the hydraulic pressure P1 of feed 1. In case the osmotic pressure pi (C1) of feed 1 is higher than the osmotic pressure pi (C2) of feed 2, the permeate is caused to flow from feed 2 to feed 1.

The degree of permeation can be calculated as permeate flux J _w. Permeate flux is defined as the volume per unit time flowing through the membrane per unit area.

Conventional RO and OsARO are different from FO, PRO and PAFO. In the RO process, the permeate flows from feed 1, which has a higher hydraulic pressure P1, to feed 2, which has a lower hydraulic pressure P2. In RO, feed 2 is initially free of solution (in most cases pure solvent such as water) and thus has no initial solute concentration C2 and corresponding osmotic pressure pi (C2). In OsARO, the permeate flows from feed 1, which has a higher osmotic pressure π (C1), to feed 2, which has a lower osmotic pressure π (C2). In some cases, the concentrations C1 and C2 of feed 1 and feed 2, respectively, are the same in OsARO. The permeate flows from the feed 1 side to the feed 2 side of the semi-permeable membrane only due to the hydraulic pressure P1 applied to feed 1 being higher than the hydraulic pressure P2 applied to feed 2.

The difference between conventional RO and OsARO is the cause of the low osmotic pressure mixture feed (C2). In the RO process, feed 2 is not introduced across the membrane; only permeate flowing from feed 1 is present on the feed 2 side of the membrane. In contrast, in OsARO, a second feed having a concentration of C2 was introduced independently into the stage, as demonstrated in fig. 1-3. This second feed reduces the osmotic pressure differential across the semi-permeable membrane, thereby reducing the hydrostatic pressure required to flow the solvent through the semi-permeable membrane, thereby producing a concentrated feed solution and a dilute feed solution.

From the above comparison, it can be seen that the OsARO process disclosed in the present invention is different from the previously known processes. Using the OsARO apparatus and techniques disclosed herein, concentrated feed 1 solution and/or dilute feed 2 solution can be obtained independently for various applications.

The OsARO process disclosed herein requires specific semi-permeable membranes and filtration modules that are different from those known in the art. In particular, the disclosed semipermeable membranes and filtration modules are configured to receive a second flow of feed solution to the second side of the membrane, while the first side of the membrane is configured to receive a first flow of feed solution. In contrast, conventional RO membranes and filtration modules are configured to receive only a single feed solution stream to only one side of the membrane. Thus, during the RO process, there is only permeate on the second side of the membrane that flows through the membrane from a single feed solution stream.

Filtration membranes are typically made of fine grained or fragile materials, which limits the effective operating pressures at which the membranes can be used. In many cases, RO membranes and filtration modules are limited by operating pressures of 70 bar or less. At such pressures, the RO membrane or filtration module will no longer produce permeate. Another reason RO modules are limited by operating pressures of 70 bar or less is that the high solute concentrations produced by the higher operating pressures increase the operating costs of the modules. This is due to the lower permeate flux produced per incremental pressure increase and the coincidental increase in membrane fouling. These effects are caused by a large concentration polarization occurring at the membrane surface, with a high solute concentration on one side of the membrane and a low solute concentration on the other side of the membrane. Since permeate quality is very important in an RO system, a typical RO module exhibits a rejection of 99 +% in order to achieve the necessary single pass RO permeate quality. RO systems operating at high solute concentrations and high pressure conditions may require a second filtration, thereby increasing the energy requirements and cost of the system.

The disclosed filtration modules suitable for use in the OsARO process are configured to overcome the operating pressure limitations inherent in conventional RO systems by introducing a second feed solution stream having an osmotic pressure sufficient to reduce the operating pressure necessary to perform the RO process or filtration step. The membrane and filtration module described in the present invention can therefore be operated at operating pressures up to 120 bar. In at least some cases, the osmotic pressure of the second feed solution stream can be equal to or less than the osmotic pressure of the first feed solution.

Membranes employed in conventional RO applications, while not configured to receive a second feed solution stream on a second side or inner bore of the membrane, are designed to provide over 99% desalination rate for brackish water RO, and typically up to 99.8% desalination rate for seawater RO, in order to desalinate the water to meet potable requirements. However, the 99 +% salt rejection criteria can be relaxed for the disclosed membranes and filtration modules suitable for use in accordance with the disclosed OsARO methods and techniques. In OsARO applications, the first feed solution stream and the second feed solution stream may be allowed to mix by passing across the membrane. Thus, the osmotic pressure difference is reduced and transmembrane flux is increased. By reducing the salt filtration parameter for the salt species of interest, the pressure required to increase or decrease salinity can be reduced, thereby saving energy.

In at least some cases, the disclosed membranes exhibit a permeate flux of at least 0.18 liters per square meter per hour (LMH) when both sides of the membrane are exposed to a flow of feed solution containing 35,000ppm solute at a temperature of 25 ℃ and a transmembrane hydraulic pressure of about 40 bar or about 600 psi. In at least some cases, the solute is NaCl or seawater.

In at least some cases, the membrane exhibits a salt rejection of between about 60% and about 90% during operation in a desalination or ZLD or near ZLD wastewater treatment system. In other cases, the membrane exhibits a salt rejection of between about 30% and about 99% or between about 40% and about 95%. In at least some cases, the disclosed membranes exhibit a salt rejection between about 60% and about 90% when both sides of the membrane are exposed to a feed solution stream comprising 200,000ppm solute at a temperature of 25 ℃ and a pressure of about 70 bar or about 1000 psi. In at least some cases, the solute is ammonium sulfate.

The disclosed membrane may be configured to operate with a hydrostatic pressure on the second side of the membrane of about 1% to about 40% of the hydrostatic pressure on the first side of the membrane. In some cases, the disclosed membranes may be configured to operate with a hydrostatic pressure on the second side of the membrane of about 1% to about 25% of the hydrostatic pressure on the first side of the membrane, or about 1% to about 5% of the hydrostatic pressure on the first side of the membrane. In at least some instances, the disclosed membranes can be configured to operate with hydrostatic pressure on the second side of the membrane within a range (encompassing any value and any subset between the upper and lower limits) of about 1%, 2%, 3%, 5%, 10%, 12%, 15% to an upper limit of about 5%, 10%, 12%, 15%, 20%, 25%, 30%, 35%, and 40% of hydrostatic pressure on the first side of the membrane.

The disclosed membrane may be configured to operate with a pressure on the first side of the membrane of about 10 bar to about 120 bar and a pressure on the second side of the membrane of about 2 bar to about 20 bar. In at least some cases, the disclosed membranes can be configured to operate with a hydrostatic pressure on the first side of the membrane within a range from a lower limit of about 10 bar, 15 bar, 20 bar, 25 bar, 30 bar, 35 bar, 40 bar, 45 bar, 50 bar, 55 bar, 60 bar, 65 bar, 70 bar, 75 bar, 80 bar, 85 bar, 90 bar, 95 bar, 100 bar to an upper limit of about 105 bar, 110 bar, 115 bar, 120 bar, 125 bar, 130 bar, 135 bar, 140 bar, 145 bar, 150 bar, 155 bar, 160 bar, 165 bar, 170 bar, 175 bar, 180 bar, 185 bar, 190 bar, 195 bar, and 200 bar (encompassing any value and any subset between the upper and lower limits).

In at least some cases, the disclosed membranes can be configured to operate with a hydrostatic pressure on the second side of the membrane within a range (encompassing any value and any subset between the upper and lower limits) from a lower limit of about 1 bar, 2 bar, 3 bar, 4 bar, 5 bar, 6 bar, 7 bar, 8 bar, 9 bar, 10 bar, 11 bar, 12 bar, 13 bar, 14 bar, 15 bar to an upper limit of about 5 bar, 6 bar, 7 bar, 8 bar, 9 bar, 10 bar, 11 bar, 12 bar, 13 bar, 14 bar, 15 bar, 16 bar, 17 bar, 18 bar, 19 bar, 20 bar, 21 bar, 22 bar, 23 bar, 24 bar, and 25 bar.

The membrane and filtration module disclosed by the invention can be combined with a conventional RO system to reduce the feed concentration of the existing RO equipment, increase the water yield and improve the water quality. Furthermore, the salinity of the brine produced by the disclosed OsARO membranes, filtration modules, and techniques is higher than that produced by conventional RO systems, thereby enabling the disclosed apparatus and methods to be used to produce concentrated feed streams for Zero Liquid Discharge (ZLD) applications or near ZLD applications.

The disclosed membranes (such as membranes 115 and 215-218 described above with reference to fig. 1 and 2) may be comprised of any semi-permeable membrane material having the ability to preferentially pass one flow component therethrough over another. The membrane may be a polymeric membrane, an inorganic membrane, a biological and inorganic composite membrane, a synthetic organic composite membrane, or any combination thereof. The polymer membrane may be formed according to the phase inversion process developed by Loeb & souriirajen to form an asymmetric membrane with a porosity and pore size gradient across the membrane. Such a membrane is capable of separating solutes from solvents, since one species diffuses across the membrane preferentially over another.

In at least some cases, the membrane can be an inorganic membrane, such as a ceramic membrane, a glass membrane, a metal membrane, a carbon membrane, a zeolite membrane, or any combination thereof. The inorganic membrane may be prepared according to a sintering process or any other method known in the art.

In some cases, the membrane may be a thin film composite membrane composed of multiple materials. In such cases, the membrane may be formed by coating a porous support layer with a semi-permeable membrane layer. In at least some cases, the thin active layer coating can be composed of the same material as the porous support material.

In at least some cases, the membrane can be a biological membrane that includes a lipid bilayer and a protein, wherein the protein is incorporated into one or more lipid bilayers and is capable of selectively transporting solutes across the membrane. In at least some cases, such biofilms may be mixed with other membranes in order to form biological and inorganic complexes, or biological and synthetic organic complexes. Examples of biological and synthetic organic composite membranes are aquaporin membranes.

The disclosed film may include an active skin on the first side of the film, or the second side of the film, or both the first and second sides of the film. As used herein, the term "active skin" refers to a portion of the membrane responsible for filtering out substances of interest in order to mitigate membrane fouling. Substances of interest may include particles, organic and inorganic materials, and microorganisms. Since the disclosed membrane is configured to receive the feed solution on both sides of the membrane, each side of the membrane may include a reactive skin for better filtration of contaminants during operation. However, in at least some instances, the membrane may or may not include a reactive skin, particularly where one or more feed solution streams are pretreated to remove contaminating materials.

The disclosed membranes can operate within a relatively narrow temperature range near ambient temperature or can be operated in conjunction with industrial processes where heating or cooling of the process stream is not always feasible. In such cases, the membranes may be constructed, at least in part, of materials suitable for higher temperatures, such as Polybenzimidazole (PBI) fibers, Polysulfone (PSU), Polyarylsulfone (PAS), Polyarylethersulfone (PAES), Polyimide (PI), polyphenylene sulfide (PPS), Polyetherketoneketone (PEKK), Polyethersulfone (PES), Polyetherimide (PEI), polyamide-imide (PAI), Polyetheretherketone (PEEK), polyphenylsulfone (PPSU), polyvinylidene fluoride (PVDF), Perfluoroalkoxyalkane (PFA), regenerated cellulose, and Fluorinated Ethylene Propylene (FEP).

The disclosed filtration module includes at least two inlet ports and at least two outlet ports. The at least one inlet port is configured to receive a flow of a first feed solution from a first feed solution source, and the at least one inlet port is configured to receive a flow of a second feed solution from a second feed solution source. The disclosed filtration module also includes at least one outlet port configured to discharge a concentrated first feed solution stream, and at least one outlet port configured to discharge a resulting permeate solution or diluted second feed solution stream.

For example, the filtration module 150 (as depicted in fig. 1) includes an inlet port 181 that provides an inlet channel for the first feed solution stream 141 to enter the first chamber 131 and be received by the first side 121 of the membrane 115. The filtration module 150 also includes a first outlet port 191 that provides an outlet for the concentrated first feed solution stream 171 to exit from the first chamber 131. The filtration module 150 also includes a second inlet port 182 that provides an inlet channel for the second feed solution stream 142 to enter the second chamber and be received by the second side 122 of the membrane 115. The filtration module 150 also includes a second outlet port 192 that provides an outlet for the diluted second feed solution stream 172 from the second chamber 132.

Although the filtration module 150 is depicted in fig. 1 as having two inlet ports and two outlet ports, for a total of four ports, any number of inlet ports and/or outlet ports is within the spirit and scope of the present disclosure, so long as there is at least one inlet port and one outlet port in fluid communication with the first side of the membrane and at least one inlet port and one outlet port in fluid communication with the second side of the membrane. For example, filtration modules having 4, 5, 6, 7, 8, 9, 10, 11, 12 to 100 ports are within the spirit and scope of the present disclosure.

The disclosed membranes may be in any form or configuration that is effective to perform the OsARO processes and techniques disclosed herein. For example, the disclosed membranes may be in the form of parallel blades, dynamic membranes, tubular ceramic membranes, tubular polymer membranes, oscillating membranes, or Disk and Tube (disks and Tube). In at least some cases, the film can be a flat sheet film of the form: spiral wound flat sheet membranes, flat frame profiles, flat sheet blades suspended in a feed solution, or folded flat sheets in a package. In other cases, the membrane may be a tubular membrane of the form: hollow fiber tubular membranes, hollow fine fiber tubular membranes, capillary tubular membranes, and double open tubular membranes without a shell.

According to at least one aspect of the present disclosure, the membrane may be a flat sheet membrane, such as the one depicted in fig. 4. Fig. 4 depicts a filtration module 400 having a housing 410, a permeate tube 455, and at least one leaflet 435 formed by a flat sheet membrane 450 arranged to form a membrane enclosure 430 surrounding a permeate spacer 425. The permeate spacer 425 includes one or more permeate channels (not shown). The outer side of the membrane envelope 430, or leaflets 435, forms a first side 460 of the membrane 450, while the inner side of the membrane envelope 430 forms a second side 470 of the membrane 450. In at least some cases, the membrane seal 430 can be a folded semi-permeable membrane sheet.

The housing 410 of the filtration module 400 includes a first inlet port 480 configured to receive a flow of a first feed solution from a first feed solution source (not shown) and a first outlet port 482 configured to discharge a flow of concentrated first feed solution from the filtration module 400. The housing 410 also includes a second inlet port 484 configured to receive a flow of the second feed solution from a second feed solution source (not shown) and a second outlet port 486 configured to discharge a flow of the diluted second feed solution.

As depicted in fig. 4, the filtration module 400 includes a permeate tube 455 disposed along an edge of a semi-permeable membrane and fluidly coupled with one or more permeate channels (not shown) in the permeate spacer 425 via one or more perforations 475 formed in the permeate tube 455. The permeate tube 455 is also coupled with a second outlet port 486 of the housing 410. The edges of the membrane envelope are sealed with an adhesive 415, except that the inside edges of the permeate spacer 425 are open to the perforations 475 of the permeate tubes 455. Each semi-permeable membrane 450 contained within the housing 410 has an outer side 460 fluidly coupled to the first inlet port 480 and an inner side 470 fluidly coupled to the permeate spacer 425 and the one or more permeate channels. The outer side 460 of the membrane 450 is configured to receive a flow of a first feed solution from a first feed solution source via a first inlet port 480. The permeate spacer 425 is fluidly coupled to the second inlet port 484, and thus, the inner side 470 of the membrane 450 is configured to receive a flow of a second feed solution from a second feed solution source via the second inlet port 484 and the permeate spacer 425. Thus, upon application of hydrostatic pressure to the first side 460 of the membrane 450, the membrane 450 is configured to pass solvent of the first feed solution stream as a permeate solution across the membrane to one or more permeate channels in the permeate spacer 425 and through the second outlet port 486 via the permeate tube 455.

The flat sheet membranes disclosed herein may have a variety of configurations as long as the flat sheet membrane includes means for flowing a flow of the second feed solution to the second side of the membrane (the inside of the membrane seal). All such configurations are within the spirit and scope of the present disclosure. Fig. 4-6 illustrate three such configurations as exemplary embodiments of the present disclosure.

As shown in fig. 4, the filtration module 400 also includes a sealing element 490 that divides the permeate tube 455 into a first permeate tube portion 457 and a second permeate tube portion 459. The first permeate tube portion 457 is fluidly coupled to the second inlet port 484, and the second permeate tube portion 459 is fluidly coupled to the second outlet port 486. The first permeate tube portion 457 is configured to receive a flow of a second feed solution from a second feed solution source via a second inlet port 484 and deliver the flow of the second feed solution through one or more perforations 475 in the first permeate tube portion 457 to one or more permeate channels in the permeate spacer 425 such that the flow of the second feed solution is in fluid communication with the inner side 470 of the semi-permeable membrane 450.

In addition, a sealing element 490 extends longitudinally from the permeate tube 455 into the permeate spacer 425 to direct the flow of the second feed solution from the first permeate tube portion 457 in a generally U-shaped path to the second permeate tube portion 459.

Fig. 5 provides an alternative embodiment of a filtration module having flat sheet membranes suitable for use in an OsARO system wherein the permeate spacer comprises a receiving chamber and a collection chamber. As depicted in fig. 5, the filtration module 500 includes a housing 510, a permeate tube 555, and at least one leaflet 535 formed by a flat sheet membrane 550 arranged to form a membrane enclosure 530 surrounding a permeate spacer 525. The permeate spacer 525 includes one or more permeate channels (not shown). The outer side of the membrane enclosure 530, or leaflets 535, forms a first side 560 of the membrane 550, while the inner side of the membrane enclosure 530 forms a second side 570 of the membrane 550. In at least some cases, the membrane seal 530 can be a folded semi-permeable membrane sheet. The edges of the film seal 530 are sealed by the adhesive 515.

The housing 510 of the filtration module 500 includes a first inlet port 580 configured to receive a flow of a first feed solution from a first feed solution source (not shown) and a first outlet port 582 configured to discharge a flow of concentrated first feed solution from the filtration module 500. Housing 510 also includes a second inlet port 584 configured to receive a flow of second feed solution from a second feed solution source (not shown) and a second outlet port 586 configured to discharge a flow of diluted second feed solution.

As shown in fig. 5, the filtration module 500 further comprises permeate tubes 555 disposed along the edges of the semi-permeable membranes 550. A first sealing element 591 disposed in the first end 552 of the permeate tube 555 divides the permeate tube 555 into a first end portion 557 and a central portion 558. The first end portion 557 is fluidly coupled to the second inlet port 584. The filtration module 500 also includes a second sealing element 592 disposed in the second end 553 of the permeate tube 555 to divide the permeate tube 555 into a second end portion 559 and a central portion 558. The second end portion 559 is fluidly coupled with the second outlet port.

Further, the first sealing element 591 extends longitudinally from the permeate tube 555 into the permeate spacer 525 to form a permeate spacer receiving portion 598 fluidly coupled with the first end portion 557 and configured to receive a flow of the second feed solution from the second feed solution source. The first sealing element 591 also includes one or more perforations 575 configured to allow the flow of the second feed solution into the permeate spacer 525 and the one or more permeate channels such that the second feed solution flow is in fluid communication with the inner side 570 of the semi-permeable membrane 550.

The second sealing element 592 extends longitudinally from the permeate tube 555 into the permeate spacer 525 to form a permeate spacer collection portion 599 fluidly coupled with the second end portion 559 via one or more perforations 575 in the second sealing element 592.

The semi-permeable membrane 550 contained within the housing 510 has an outer side 560 fluidly coupled to the first inlet port 580, and an inner side 570 fluidly coupled to the permeate spacer 525 and the one or more permeate channels. The outer side 560 of the membrane 550 is configured to receive a flow of a first feed solution from a first feed solution source via a first inlet port 580. The permeate spacer 525 is fluidly coupled with the second inlet port 584 via the permeate spacer receiving portion 598, and thus, the inner side 570 of the membrane 550 is configured to receive a flow of the second feed solution from the second feed solution source via the second inlet port 584, the permeate spacer receiving portion 598, and the permeate spacer 525. Thus, upon application of hydrostatic pressure to the first side 560 of the membrane 550, the membrane 550 is configured to pass solvent of the first feed solution stream across the membrane 550 in the form of a permeate solution to one or more permeate channels in the permeate spacer 525, and through the second outlet port 586 via the permeate spacer collection portion 599 and the second end portion 559 of the permeate tube 555.

Fig. 6 provides an alternative embodiment of a flat sheet membrane filtration module suitable for use in an OsARO system, the flat sheet membrane filtration module having a second tube. As depicted in fig. 6, the filtration module 600 includes a housing 610, a permeate tube 655, and at least one leaflet 635 formed by a flat sheet membrane 650 arranged to form a membrane enclosure 630 surrounding a permeate spacer 625. The permeate spacer 625 includes one or more permeate channels (not shown). The outer side of the membrane seal 630, or leaflets 635, forms a first side 660 of the membrane 650, while the inner side of the membrane seal 630 forms a second side 670 of the membrane 650. In at least some cases, the membrane seal 630 can be a folded semi-permeable membrane sheet.

The housing 610 of the filtration module 600 includes a first inlet port 680 configured to receive a flow of a first feed solution from a first feed solution source (not shown) and a first outlet port 682 configured to discharge a flow of concentrated first feed solution from the filtration module 600. The housing 610 also includes a second inlet port 684 configured to receive a flow of the second feed solution from a second feed solution source (not shown), and a second outlet port 686 configured to discharge a flow of the diluted second feed solution.

As depicted in fig. 6, the filtration module 600 includes permeate tubes 655 disposed along the edges of the semi-permeable membrane and fluidly coupled with one or more permeate channels (not shown) in the permeate spacer 625 via one or more perforations 675 formed in the permeate tubes 655. The permeate tube 655 is also coupled with a second outlet port 686 of the housing 610. The filtration module 600 further includes a second tube 657 disposed along an edge of the semi-permeable membrane 650 opposite the permeate tube 655. The second tubes 657 are fluidly coupled with the permeate spacer 625 and the one or more permeate channels via one or more perforations 675 formed in the second tubes 657. The second tube 657 is also fluidly coupled with a second inlet port 684. The edges of the membrane seal 630 are sealed by the adhesive 615, except that the inside edge of the permeate spacer 625 opens into the perforations 675 of the permeate tubes 655 and the opposite inside edge of the permeate spacer 625 opens into the perforations 675 of the second tubes 657. The second tube 657 is configured to receive a flow of a second feed solution from a second feed solution source via a second inlet port 684 and deliver the flow of the second feed solution through one or more perforations 675 in the second tube 657 to the permeate spacer such that the flow of the second feed solution is in fluid communication with the interior side 670 of the membrane 650.

Each semi-permeable membrane 650 housed in the housing 610 has an outer side 660 fluidly coupled to a first inlet port 680, and an inner side 670 fluidly coupled to a permeate spacer 625 and one or more permeate channels. The outer side 660 of the membrane 650 is configured to receive a flow of a first feed solution from a first feed solution source via a first inlet port 680. The permeate spacer 625 is fluidly coupled with the second inlet port 684 via a second tube 657, and thus, the inner side 670 of the membrane 650 is configured to receive a second feed solution stream from a second feed solution source via the second inlet port 684, the second tube 657, and the permeate spacer 625. Thus, upon application of hydrostatic pressure to the first side 660 of the membrane 650, the membrane 650 is configured to transfer solvent of the first feed solution stream as a permeate solution across the membrane to the one or more permeate channels in the permeate spacer 625 and through the second outlet port 686 via the perforations 675 in the permeate tube 655.

Fig. 7 is an exploded view of a flat sheet membrane envelope according to an example embodiment of the present disclosure. As depicted in fig. 7, the filtration module 700 includes a permeate tube 755 and leaflets 735 formed of flat sheet membranes 750 arranged to form a membrane enclosure 730 around the permeate spacer 725. The leaflets 735 may be formed from a single flat sheet membrane 750 that is folded to form one edge of the leaflets 735 and secured or fastened to the permeate tube 755, or alternatively the leaflets 735 may be formed from first and second

flat sheet membranes

750, 750 that are arranged to form a membrane enclosure 730 around the spacer 725 and sealed or glued at two or more edges. The edges of the membrane seal are sealed with adhesive except that the inside edge of the permeate spacer 725 is open to the perforations (not shown) of the permeate tube 755.

The flat sheet film 750 may include an active skin 792 on one or more sides of the flat sheet film 750. The flat sheet membrane 750 may also include a perforated portion 794 and a support structure 796. The support structure 796 may be a woven or non-woven structure. The permeate spacer 725 includes one or more permeate channels 788.

The outer side of the film seal 730, or leaflets 735, forms a first side 760 of the film 750, while the inner side of the film seal 730 forms a second side 770 of the film 750. The permeate tubes 755 are disposed along the edges of the semi-permeable membrane 750 and are fluidly coupled with one or more permeate channels 788 in the permeate spacer 725 via one or more perforations (not shown) formed in the permeate tubes 755. Upon application of hydrostatic pressure to the first side 760 of the membrane 750, the membrane 750 is configured to transfer solvent of the first feed solution stream in the form of a permeate solution across the membrane 750 to one or more permeate channels 788 in the permeate spacer 725 and through a second outlet port (not shown) via permeate tube 755.

Fig. 8 is an exploded view of a flat sheet membrane envelope filtration module with feed spacers according to an example embodiment of the present disclosure. As depicted in fig. 8, the filtration module 800 has similar features to fig. 7, but additionally includes a feed spacer 875 having a feed spacer channel 878 that provides flow of the first feed solution stream such that the first feed solution stream flows around the leaflets 835 and contacts the first side 860 of the membrane 850. In at least some cases, filtration module 800 is comprised of a plurality of leaflets 835 separated by at least one feed spacer 875. The permeate spacer 825 includes permeate channels 888 that provide flow of the second feed solution stream and permeate over the interior side of each leaflet 835 and contact with the second side 870 of the membrane 850. The feed spacer 875 can be fluidly coupled to one or more first inlet ports (not shown) and one or more first outlet ports (not shown).

As depicted in fig. 8, the filtration module 800 includes a permeate tube 855 and leaflets 835 formed by flat sheet membranes 850 arranged to form a membrane enclosure 830 around the permeate spacer 825. The leaflets 835 may be formed by a single flat sheet membrane 850 that is folded to form one edge of the leaflet 835 and secured or fastened to the permeate tube 855, or alternatively the leaflets 835 may be formed by first and second flat sheet membranes 850 arranged to form a membrane enclosure 830 around the spacer 825 and sealed or glued at two or more edges. The edges of the membrane seal are sealed with adhesive except that the inside edge of the permeate spacer 825 is open to the perforations (not shown) of the permeate tube 855.

The flat sheet membrane 850 may include an active skin 892 on one or more sides of the flat sheet membrane 850. The flat sheet membrane 850 may also include a porous portion 894 and a support structure 896. Support structure 896 may be a woven or non-woven structure. The permeate spacer 825 includes one or more permeate channels 888.

The outer side of the membrane envelope 830, or leaflets 835, forms a first side 860 of the membrane 850, while the inner side of the membrane envelope 830 forms a second side 870 of the membrane 850. The permeate tube 855 is disposed along the edge of the semi-permeable membrane 850 and is fluidly coupled to one or more permeate channels 888 in the permeate spacer 825 via one or more perforations (not shown) formed in the permeate tube 855. Upon application of hydrostatic pressure to the first side 860 of the membrane 850, the membrane 850 is configured to pass solvent of the first feed solution stream in the form of a permeate solution through the membrane 850 to the one or more permeate channels 888 in the permeate spacer 825 and through a second outlet port (not shown) via a permeate tube 855.

In at least some cases, the leaflets disclosed herein (such as

leaflets

435, 535, 635, 735, and 835 in fig. 4-8) can be repeatedly wound on a permeate tube to form a rolled or spiral wound flat sheet membrane, as shown in fig. 9. As depicted in fig. 9, the spiral wound flat sheet membrane module 900 includes a spiral wound flat sheet membrane 905 repeatedly wound on a permeate tube 955. The spiral wound flat sheet module 900 also includes a housing 910 around which a flat sheet film 905 is wound. The housing 910 includes a first inlet port 980 configured to receive a flow of the first feed solution from a first feed solution source (not shown) and a first outlet port 982 configured to discharge a flow of the concentrated first feed solution from the filtration module 900. The housing 910 also includes a second inlet port 984 configured to receive a flow of a second feed solution from a second feed solution source (not shown) and a second outlet port 986 configured to discharge a flow of a diluted second feed solution.

The disclosed flat sheet membranes may be configured to exhibit salt rejection levels of about 30% to about 99.9%, depending on the type and application of salt. In at least some instances, the disclosed flat sheet membranes can exhibit salt rejection levels of about 40% to about 95% or about 60% to about 90%. The disclosed flat sheet membrane is capable of operating with a pressure on the outside of the blade of about 10 bar to about 120 bar and a pressure on the inside of the blade of about 2 bar to about 20 bar. In other cases, the flat sheet membranes may be operated with a pressure on the outside of the blade of about 30 bar to about 80 bar and a pressure on the inside of the blade of about 2 bar to about 20 bar.

According to at least one aspect of the present disclosure, the membrane may be a tubular hollow fiber membrane having an inner bore and an outer shell, as shown in fig. 10. Fig. 10 is a diagram of a tubular hollow fiber membrane module 1000 according to an example embodiment of the present disclosure. As depicted in fig. 10, the tubular hollow fiber membrane module 1000 includes a housing 1010 and a plurality of tubular hollow fiber membranes 1050. Each tubular hollow fiber membrane 1050 includes an outer housing 1002 and an inner bore 1004. First side 1060 of membrane 1050 may be the outer surface of outer housing 1002 and second side 1070 of membrane 1050 may be the inner surface of inner bore 1004 of tubular hollow fiber membrane 1050. During operation, upon application of hydrostatic pressure to the first side 1060 of the membrane 1050, the permeate solution passes into the inner pores 1004 of the membrane 1050. Each tubular hollow fiber membrane 1050 is open at both ends, and permeate may flow out from one end or both ends of the hollow fiber membrane 1050 depending on the configuration of the filtration module 1000. In at least some cases, each tubular hollow fiber membrane 1050 is made at least in part of cellulose triacetate.

Each tubular hollow fiber membrane 1050 is configured to receive a flow of a second feed solution into bore 1004 such that the flow of the second feed solution contacts the inner surface of bore 1004 and thus second side 1070 of membrane 1050. The hydrostatic pressure exerted on the housing causes the second feed solution stream to mix with the permeate passing through the membrane 1050 wall from the first side of the membrane 1060, forming a diluted second feed solution stream. Thus, the diluted second feed solution stream exits the inner bore 1004 of the tubular hollow fiber membranes 1050, while the concentrated first feed solution stream exits the shell side 1070 of the tubular hollow fiber membranes 1050.

The housing 1010 includes a first inlet port 1080 configured to receive a flow of a first feed solution from a first feed solution source (not shown) and a first outlet port 1082 configured to discharge a concentrated flow of the first feed solution from the filtration module 1000. Housing 1010 also includes a second inlet port 1084 configured to receive a flow of a second feed solution from a second feed solution source (not shown). Second inlet port 1084 is fluidly coupled with one or more bores 1004 of tubular hollow fiber membranes 1050. The housing 1010 also includes a second outlet port 1086 configured to receive a flow of diluted second feed solution from the one or more bores 1004 of the tubular hollow fiber membranes 1050 and discharge the flow of diluted second feed solution from the filtration module 1000. The potting material 1095 serves to keep the flow of the second feed solution separate from the flow of the first feed solution and to facilitate the flow of the second feed solution through the second inlet port 1084 to the inner bore 1004 of the tubular hollow fiber membranes 1050 or over the opposite end of the module 1000, facilitating the flow of the diluted second feed solution from the inner bore 1004 of the tubular hollow fiber membranes 1050 to the second outlet port 986 and out of the module 1000.

While tubular hollow fiber membranes have been used in conventional RO applications and are not configured to receive a second feed solution stream on the second side or inner bore of the membrane, such tubular hollow fiber membranes are designed to provide desalination rates of greater than 99% for brackish water RO and typically up to 99.8% for seawater RO in order to desalinate the water to meet potable requirements. However, the 99 +% salt rejection criteria can be relaxed for the disclosed membranes and filtration modules suitable for use in accordance with the disclosed OsARO methods and techniques. In OsARO applications, the first feed solution stream and the second feed solution stream may be allowed to mix by passing across the membrane. Thus, the osmotic pressure difference is reduced and transmembrane flux is increased. By reducing the salt filtration parameter for the salt species of interest, the pressure required to increase or decrease salinity can be reduced, thereby saving energy. The disclosed tubular hollow fiber membranes can be configured to exhibit salt rejection levels between about 30% and about 99.9%, depending on the type and application of the salt. In at least some instances, the disclosed tubular hollow fiber membranes can exhibit a salt rejection level of between about 40% and about 95%, or between about 60% and about 90%.

The disclosed tubular hollow fiber membranes are capable of operating with a pressure between about 10 bar and about 120 bar on the shell side and a pressure between about 2 bar and about 20 bar on the inner bore side of the membrane. In other cases, the tubular hollow fiber membranes may be operated with a pressure on the shell side of the membrane of from about 30 bar to about 80 bar. The tubular hollow fiber membrane may have an inner diameter of about 63 μm to about 2,000 μm. In some cases, the tubular hollow fiber membrane may have an inner diameter of about 85 μm to about 230 μm or about 100 μm to about 150 μm. The thickness of the tubular hollow fiber membranes can be varied to support an operating pressure differential of about 10 bar to about 120 bar, depending on the application.

The embodiments shown and described above are merely examples. Accordingly, many such details are neither shown nor described. Although a number of features and advantages of the present technology have been set forth in the foregoing description, together with details of the structure and function of the disclosure, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. It will therefore be appreciated that the embodiments described above may be modified within the scope of the appended claims.

Claims

1. A filtration module, comprising:

a semi-permeable membrane comprising a first side and a second side, wherein the first side is configured to receive a flow of a first feed solution from a first feed solution source and the second side is configured to receive a flow of a second feed solution from a second feed solution source, the semi-permeable membrane arranged to form a membrane seal around a permeate spacer;

wherein the semi-permeable membrane is configured to pass a solvent of the first feed solution stream from the first side of the membrane to the second side of the membrane as a permeate solution upon application of hydrostatic pressure to the first and second sides of the membrane, wherein the permeate solution passes to one or more permeate channels in the permeate spacer upon application of hydrostatic pressure to the first side of the membrane;

a permeate tube disposed along an edge of the semi-permeable membrane and fluidly coupled to the one or more permeate channels, the permeate tube including a first sealing element disposed in a first end of the permeate tube so as to divide the permeate tube into a first end portion and a central portion, and a second sealing element disposed in a second end of the permeate tube so as to divide the permeate tube into a second end portion and a central portion, wherein the first end portion is fluidly coupled to a second inlet port and the second end portion is fluidly coupled to a second outlet port,

Wherein the first sealing element extends longitudinally from the permeate tube into the permeate spacer to form a permeate spacer receiving portion that is fluidly coupled with the first end portion and configured to receive the second feed solution stream from the second feed solution source, the first sealing element comprising one or more perforations configured to allow the second feed solution stream to flow into the permeate spacer and the one or more permeate channels such that the second feed solution stream is in fluid communication with an inner side of each semi-permeable membrane; and wherein the second sealing element extends longitudinally from the permeate tube into the permeate spacer to form a permeate spacer collection portion fluidly coupled with the second end portion via one or more perforations in the second sealing element,

wherein the semi-permeable membrane is configured to operate at a hydrostatic pressure on the second side that is 1% to 40% of the hydrostatic pressure on the first side of the membrane.

2. The module of claim 1, wherein the membrane exhibits a salt rejection rate of 60% to 90% during operation in a desalination, ZLD, or near ZLD wastewater treatment system.

3. An apparatus comprising the module of claim 1, the apparatus further comprising:

a first feed solution source; and

a second feed solution source;

wherein the first feed solution stream has a first solute concentration and a first osmotic pressure and the second feed solution stream has a second solute concentration and a second osmotic pressure, the first osmotic pressure being greater than or equal to the second osmotic pressure and the second feed solution stream having an osmotic pressure greater than the permeate solution,

wherein the first feed solution source is configured to provide a hydrostatic pressure of 10 to 120 bar on the shell side of the membrane and the second feed solution source is configured to provide a hydrostatic pressure of 2 to 20 bar on the inner pore side of the membrane, and

the membrane envelope and the permeate spacer constitute leaflets, the first side of the membrane constituting an outer side of the membrane envelope and the second side of the membrane constituting an inner side of the membrane envelope, and wherein upon application of hydrostatic pressure to the first side of the membrane, the permeate solution is transferred to one or more permeate channels in the permeate spacer.

4. The apparatus of claim 3, further comprising a permeate tube fluidly coupled with the permeate spacer, wherein the leaflets are repeatedly wound on the permeate tube in a roll.

5. A desalination, Zero Liquid Discharge (ZLD) or near ZLD wastewater treatment system comprising the module of claim 1, wherein the membrane of the module exhibits a desalination rate of 60% to 90% during operation in the desalination, ZLD or near ZLD wastewater treatment system.

6. The module of claim 1, wherein the membrane comprises a membrane in a form selected from the group consisting of: parallel blades, dynamic membranes, tubular ceramic membranes, tubular polymer membranes, oscillating membranes, and coiled tubes.

7. The module of claim 1, wherein the membrane comprises:

a flat sheet membrane having a configuration selected from the group consisting of: spiral winding, plate frame type, flat blade suspended in feed solution and folded flat sheet in package; or

A tubular membrane having a configuration selected from the group consisting of: hollow fibers, hollow fine fibers, tubes, capillaries, and double-open tubular membranes without a shell.

8. The module of claim 1, wherein the membrane is a biological membrane comprising a lipid bilayer and a protein, wherein the protein is incorporated into one or more lipid bilayers and is capable of selectively transporting solutes across the membrane.

9. A filtration module, comprising:

a first chamber and a second chamber;

a semi-permeable membrane disposed at an interface between the first chamber and the second chamber, the semi-permeable membrane having a first side in fluid communication with the first chamber and a second side in fluid communication with the second chamber, wherein the membrane is arranged to form a membrane enclosure around the second chamber;

wherein the first chamber is configured to receive a first flow of feed solution from a first source of feed solution and the second chamber is configured to receive a second flow of feed solution from a second source of feed solution;

10. A filtration module in accordance with claim 9,

wherein the first chamber comprises a first inlet port configured to receive a flow of first feed solution from the first feed solution source and a first outlet port configured to discharge a flow of concentrated first feed solution; and is

Wherein the second chamber comprises a second inlet port configured to receive a flow of a second feed solution from the second feed solution source and a second outlet port configured to discharge the produced permeate solution.

11. The module of claim 9, wherein the membrane exhibits a permeate flux of at least 0.18 liters per square meter per hour when the first side of the membrane is exposed to a first feed solution stream comprising 35,000ppm solute at a temperature of 25 ℃ and a pressure of 40 bar.

12. The module of claim 9, wherein the membrane is a tubular hollow fiber membrane having an inner bore and an outer housing, the first side of the membrane comprising an outer surface of the outer housing and the second side of the membrane comprising an inner surface of the inner bore, wherein the permeate solution passes to the inner bore of the membrane upon application of hydrostatic pressure to the first side of the membrane.

13. The module of claim 9, wherein the membrane enclosure and the second chamber constitute leaflets, the first side of the membrane constituting an outer side of the membrane enclosure in fluid communication with the first chamber and the second side of the membrane constituting an inner side of the membrane enclosure in fluid communication with the second chamber, and wherein the permeate solution passes to the second chamber upon application of hydrostatic pressure to the first side of the membrane.